Interactive Ruby Shell

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Interactive Ruby Shell
Screenshot
Interactive Ruby Shell.png
The screenshot session as same as the article example
Developer(s)Keiju Ishitsuka
Stable release
0.9.6 / June 30, 2009; 9 years ago (2009-06-30)
Written inRuby
Operating systemCross-platform
PlatformRuby interpreter
TypeRuby shell
LicenseRuby License
BSD License
Websitewww.ruby-lang.org/en/

Interactive Ruby Shell (IRB or irb) is a REPL for programming in the object-oriented scripting language Ruby. The abbreviation irb comes from the fact that the filename extension for Ruby is ".rb", although interactive Ruby files do not have an extension of ".irb".

The program is launched from a command line and allows the execution of Ruby commands with immediate response, experimenting in real-time. It features command history, line editing capabilities, and job control, and is able to communicate directly as a shell script over the Internet and interact with a live server. It was developed by Keiju Ishitsuka.

Syntax and use[edit]

Syntax:

irb [ options ] [ programfile ] [ argument... ]

Example:

irb(main):001:0> n = 5
=> 5
irb(main):002:0> def fact(n)
irb(main):003:1>   if n <= 1
irb(main):004:2>     1
irb(main):005:2>   else
irb(main):006:2*     n * fact(n - 1)
irb(main):007:2>   end
irb(main):008:1> end
=> :fact
irb(main):009:0> fact(n)
=> 120

irb(main):001:0> class Cat
irb(main):002:1>   def meow
irb(main):003:2>     puts 'The cat meows.'
irb(main):004:2>   end
irb(main):005:1> end
=> :meow

irb(main):006:0> Cat.new.meow
The cat meows.

See also[edit]

External links[edit]